I have a Precision 4iiii power meter. Works great. No complaints.

I have the power meter interfaced with my Garmin 520. The 520 reads the watts output while I'm riding and when I view the ride after, I see my power output, average, etc.

But when it comes to the screen showing L/R balance, I am seeing this:



This doesn't make sense to me because:

• The power meter is on the left side of my bike
• I thought single sided power meters compensated for being only on one crank arm.

Am I missing something here? Anyone have any insight? Thank you.

If by compensate you mean double the measured output, yes.

No idea why it's attributing power to the wrong side, though. Interesting!

Maybe it's British?

Who cares? Looking at balance with a 1 sided power meter is useless anyway.

I care I want to make sure everything is working properly.

I don't see a reason to be concerned about it, but have you poked through the 4iiii app?

The L/R data you see is not applicable and won't tell you whether the power meter is working properly. Best way to test is to borrow a powertap from someone and an extra head unit and compare the data you get from both powermeters. Everything else relies on faith and guesswork.

[MENTION=185471]WhyFi[/MENTION] Yeah, I have a phone call in to 4iiii to see what they can tell me.

[MENTION=127275]gregf83[/MENTION] Agreed. But like I said if the power meter is reporting power coming from the right leg, and the crank is on the left, something is likely wrong. As I have approx 6mos left of warranty, I want to make sure the unit is functioning as it should.

Quick update.

I called 4iiii and they tell me that others are having the same issue. Seems the most recent software update is the cause. The PM still function as it should though, so no worries there. According to 4iiii they are working on a fix.

Still no fix, I understand the data in this case would be fake or useless, but I would rather see nothing (like some nul value or something) or simulated 50-50 than 0-100, and having the 100 be on the wrong side is unsightly as well.

4iiii told me just hide that field in my computer... my issue is that no matter what bad data is being sent and recorded, and you can't ignore it when you look on Garmin Connect.

Even though it's a minor issue they should fix it. Especially if other single-sided units (Stages, Vector, whatever) don't have the same poor behavior.

[MENTION=468484]jetdog9[/MENTION] Thanks for the follow-up. I was going to reach out to 4iiii and see if a fix had been issued. Guess not. I find the issue with the left sided PM to be REALLY annoying. And hiding the field doesn't help as, like you said, when you're in GC the problem is still there.

This is disappointing service from 4iiii, especially because I bought the PM after reading all the positive reviews about both the PM and the company.

Hi guys, I have got my new Precision single side power meter and tried today. It has exactly the same problem. Do you have any news about whether it will be fixed?

Funny you should ask. I sent them an email just this week and here is what they replied with:

--
Thank you for reaching out.

This is a known issue with the latest firmware of our powermeters where it is measuring an incorrect L/R balance when it is not needed at all since it is a left-only powermeter. In theory, the L/R balance should be 100/0 as it is only measuring your power from your left leg. We are working on a new firmware update to address this.

For now, you can simply ignore the erroneous L/R balance metric. Your total power output from the powermeter is correct and it is only the L/R balance that is in error.

Please let me know if you have any further questions

Thank you very much for the information. Hope the new firmware will be available soon. It's been such a long time but they are still trying to fix it...